U.S. Pat. No. 3,871,554 discloses an eyewash dispenser having a collapsible liquid container disposed in a fixed frame. A preloaded spring is disposed between the frame and the container. When the eyewash dispenser is to be used, the spring is released by means of a rod-like release mechanism. When using the eyewash dispenser disclosed in U.S. Pat. No. 3,871,554, the user holds a handle in the frame with one hand while he releases the spring with the other by pressing on the release rod. It is difficult for the user to release the spring without using both hands.
Eyewash dispensers are often used at workplaces where work is done with liquids which, if they come into contact with the eyes, can easily cause injury if the hazardous liquid is not quickly neutralized or removed. It is then essential that the eyewash dispenser that is intended to be used to prevent eye injury when an accident occurs should be readily accessible, easy to grip and easy to handle and can be made to discharge its contents by means of a simple motion.
It is also essential that the eyewash dispenser can be held and activated with only one hand so that the accident victim can hold the eyelid open with the other hand thereby permitting the neutralizing liquid to irrigate the eyes.
Another requirement that should be made on the eyewash dispenser is that the liquid is hygienically contained and can be expressed in spray form over an extended period of time and under constant pressure. The eyewash dispenser should also be configured so that it can be used without modification for different types of flushing liquid and so that spent parts of the eyewash dispenser are easy to replace.